\r\n\r\nThe most common way to control a computer is through a mouse, but a mouse requires lifting your hand and moving your arm. A more ergonomic solution is to use a trackball, which lets your hand rest in one place. Although trackballs aren\u2019t as popular as a mouse, the Logitech M570 wireless trackball might make you change your mind.\r\n\r\nThis wireless trackball consists of the trackball itself and Logitech\u2019s tiny Unifying receiver that plugs into a USB port. This Unifying receiver works with all of Logitech\u2019s other wireless products such as keyboards and mice, so if you lose it (which is easy to do since it\u2019s so small), you can always get a replacement wireless receiver easily. The Unifying receiver lets you connect to both a Windows or Mac OS X computer from up to six feet away.\r\n\r\nOne main advantage of the Unifying receiver\u2019s small size is that it allows you to keep it plugged into a laptop computer without forcing you to remove it every time you need to pack your laptop back in its case. The Unifying receiver\u2019s small size makes it nearly flush with any laptop\u2019s side so you can just plug it into your computer once and forget about it.\r\n\r\nFor those times when you do need to unplug the Unifying receiver, the trackball\u2019s battery compartment includes a special slot for holding the receiver securely in place.\r\n\r\nThe Unifying receiver can be transported inside the battery compartment.\r\n\r\nTo power the trackball, you just need a single AA battery, which Logitech claims will last up to 18 months. (For your convenience, Logitech even includes a single AA battery that\u2019s already installed inside the trackball.) To further conserve power when you\u2019re not using the trackball, you can slide an On\/Off switch to turn the trackball off completely.\r\n\r\nUsing the trackball is extremely comfortable. Four rubber feet on the bottom of the trackball hold it securely in place on almost any surface. Besides the traditional left and right mouse buttons and a middle scroll wheel, the trackball also offers a Back and Forward button for jumping backwards and forwards inside any browser such as Internet Explorer, Firefox, Opera, or Safari.\r\n\r\nThese Back and Forward buttons worked automatically under Windows 7, but they won\u2019t work under Mac OS X until you first download a free Logitech Control Center program, which lets you configure how the trackball behaves.\r\n\r\nTo make the trackball\u2019s Back and Forward buttons work on Mac OS X, you need to download free software from Logitech.\r\n\r\nThe trackball\u2019s shape is specifically geared towards right-handed users who can comfortably manipulate the trackball with their thumb while pressing the left and right mouse buttons with their index and middle finger. Left-handed users can still use the trackball, but it may feel more awkward manipulating the trackball with your pinky.\r\n\r\nThe trackball, left and right mouse buttons, and scroll wheel work as expected. Using the Back and Forward buttons to flip through web pages in a browser is a nice added convenience so you don\u2019t have to scroll and click the Back and Forward buttons in your browser all the time.\r\n\r\nLogitech\u2019s M570 wireless trackball is much less tiring to use than a traditional mouse with the added advantage of its wireless capabilities, which lets you place and use the trackball anywhere near your computer. The additional of special Back and Forward browser buttons makes the trackball faster than a mouse for heavy web users.\r\n\r\nDespite all of its advantages, this trackball may still not change the minds of those who prefer the mouse over scrolling the trackball with their thumb, which in itself can get nearly as tiring as moving your arm to manipulate a mouse. If you aren\u2019t convinced about the benefits of a trackball, the Logitech M570 Wireless Trackball may not change your mind. However, if you\u2019re looking for an alternative to a mouse and want a versatile trackball, Logitech\u2019s latest wireless trackball will likely meet your needs.\r\n\r\nPros:\r\n\r\n\tSingle AA battery lasts up to 18 months\r\n\tErgonomic shape\r\n\tSpecial Back and Forward buttons that works with a variety of browsers including Internet Explorer, Firefox, Opera, and Safari\r\n\tWorks with both Windows XP\/Vista\/Windows 7 and Mac OS X\r\n\tUSB wireless receiver can be tucked safely inside the trackball for transport\r\n\tOn\/off switch to conserve battery power\r\n\tRubber feet holds the trackball secure on almost any surface\r\n\r\nCons:\r\n\r\n\tDesigned for right-handed users, left-handed users may find it clumsier to use\r\n\tMac OS X requires an additional free download to make the Back and Forward browser buttons work\r\n\r\nAmazon has the Logitech M570 Wireless Trackball for $50.